[Rd] Macintosh Transperancy (PR#11511)

[brdvance at gmail.com]

Full_Name: Brad Vance
Version: 2.7.0
OS: 10.5.2
Submission from: (NULL) (71.123.195.202)


Problem : When drawing transperant points with lines thick-lines(lwd>1) + fill
(pch=21-25), it looks like the line is transperantly overlayed over the fill,
making it look like 2-lines surround the fill (each a different color).  I
actually think that this is a nice OPTIONAL way to draw the points (even as
default), but since I could not discover how to turn it off, I decided to issue
the ticket.  In this option can see on the default-quartz device as well as
PDF-device.

Solution : Have the entire point-object designed/drawn as if there is
no-transparency, then make the composite object transparent.   Optionally figure
out an option to determine whether to apply transperancy as a group (to the
entire object) or separately (as it is now). 

Code : 
> df <- data.frame(X=rnorm(50),Y=rnorm(50))
> plot(X~Y,data=df,pch=c(21,22,23,24,25),cex=5,col="#00FF0055",bg="#FF000055",lwd=6)

Thanks,
-Brad Vance